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Garden Observatory

A small roll-off-roof observatory dedicated to webcam imaging

After 3 years of using my concrete pillar under open air, experiencing different weather and a somewhat lengthy procedure in taking the C8 OTA out for cooling and in again after observation, I finally got around to make an observatory. As I am no carpenter, it had to be simple. I chose to modify a garden shed set. I judged it almost ideal in (small) size and simplicity. Of course, it turned out to be a bit more complicated than I had thought!!

To see the roof moving as a GIF animation, click .

The observatory in steps

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From the start, I was a bit tired of drowning in snow...
I could not have the scope permanently mounted, and besides my feet sometimes got cold...
One day, I saw this Dutch garden shed. I could get it delivered as a flat package.
Therefore, one summer day ...
... things started to happen.
After a while, it begins to look like a garden shed.

Time to make plans for the roof which must be able to roll on-off. Here is a mock-up roof that also served as temporary rain protection when covered with plastic.

Holes for the poles have been dug (at left), and the walls have been painted once.
Inside view. Horizontal wooden beams for the roof to roll on, just over the window (which is lowered one layer relative to drawing) are supported by other 2x4" wooden poles. The poles rest on the 2x4" floor frame . Marks indicate where a cut must be made in the side wall to accommodate the 2x5" wooden beam to carry a steel U-profile serving as wheel track for the roof.
Testing the steel U-profile layout after mounting the horizontal beam extending from the shed.
4x4" wooden poles will carry the roof when rolled open.
The roof shall roll sideways. Testing the scope height vs. observatory walls shows that there is little loss of sky as compared to earlier.
Walls and structure for roof support complete with steel tracks. Just waiting for the roof. Looks like the space inside will be quite sufficient for one or two persons.
Investigating the roof design and system for carrying it on wheels. The dark impregnated 2x4" beams are add-ons. They are supported by wheels and they support the lower roof beams. The front and back walls are screwed to the wheel beams.
Roof taking shape. Pre-cut roof profiles are nailed to the roof beams.
Time to check the pillar adapter. This one was made 3 years ago and has got a fresh layer of paint. It is custom made to accept a Vixen tripod head.
The tripod head must be level to make drift alignment as painless as possible.
This Vixen GPDX has got a new home!
Moment of truth. Yes, the roof clears the telescope with a reasonable margin when telescope is "parked". There is room enough to allow an OTA upgrade here ....

The clearance between walls and roof will later be covered to avoid rain/wind/snow coming in. Also the roof needs to be secured against heavy wind, even though this is a fairly protected location.

Looking south with a dew cap on the C8
A closer look at the parking position. An idea is to create a feature in my MTSca GOTO program to park the scope. That way the scope will never have to be manually moved, and the PEC table in my MTSca controller can then be re-used between observation sessions.

First Light

Official first light was August 9, 2004. The night was warm (more than 20C all night) and pretty dry. The sky was clear and ideal for collimation and drift alignment. I got the drift down to about 0.5 seconds of arc per minute, and then took these test images:

A picture of Ring Nebula (M57).

A picture of Supernova SN2004dj.